A massive residential building stands on the outskirts of town, on a lot that was once home to an abandoned factory. There have been many dark rumors about this place lately, about the body of a teenage girl that was found there, and about the strange supernatural incidents that some have witnessed...A timid college girl named Rin has just moved into one of the residences in the building. One night, she sees a huge insect coming out of the arm of an old woman who’ s being taken away by an ambulance. Curious about what she saw, she goes to a library, where she meets a folklorist named Tokiyo. From him she learns that there have been sightings of strange insects in this area in the past as well. These insects are called “Spirit Bugs”, and they have existed in secret since ancient times.